Hi Ric,
Welcome to a fellow Brisbanite.
I can't see the crack of which you speak. is it in the nut or the fretboard or the headstock?
Probably best if you start a build diary in that section so we can follow along.
Nice mock build by the way, have you had a chance to check the scale length? sometime you need to re-position the bridge on the TL kits slightly.